Congenital CD34-positive granular cell dendrocytosis

Congenital cutaneous non-neural granular cell tumor mimicking herpetic infection: Case report and review of the literature

We present a case of a female neonate with a cluster of six skin colored to yellowish pseudovesicular papules on her right forearm present since birth, initially thought to be a herpes simplex virus infection. Punch biopsy with immunostaining revealed a diagnosis of S100-negative, CD163-positive congenital cutaneous non-neural granular cell tumor. Only four other reports are presented in the literature of this entity, three of which also presented on the arm with somewhat similar clinical findings. We briefly reviewed the subtypes of classic and S100-negative non-neural granular cell tumors.

Congenital Granular Cell Tumor of the Arm: A Rare Presentation

Congenital granular cell tumors are uncommon benign tumors of newborns that mainly affect oral mucosa, especially the maxillary alveolar ridge. They are predominantly seen in female newborns, and cutaneous involvement is extremely rare. In this report, we present a case of congenital granular cell tumor on the arm of one of the male monozygotic twins and discuss the differential diagnosis of granular cell phenotype.

Medallion-like dermal dendrocytoma

Medallion-like dermal dendrocytoma is a benign cutaneous neoplasm that mimics dermatofibrosarcoma protuberans histologically. The distinction between these two entities is critical to prevent unnecessary wide excisions. Herein we describe an acquired MLDD in a 55-year-old female.

Medallion-like dermal dendrocyte hamartoma: a case misdiagnosed as neurofibroma

Medallion-like dermal dendrocyte hamartoma is a rare congenital lesion, comprised of a benign dermal proliferation of fusiform cells that stain positive for CD34, often positive for factor XIIIa, and negative for S100. It has a highly characteristic clinical presentation consisting of a well-circumscribed atrophic and wrinkled patch located on the upper trunk or neck that remains stable with time. We report a case of an 11-year-old boy with a typical medallion-like dermal dendrocyte hamartoma on the nape of the neck that was previously misdiagnosed as neurofibroma on the basis of initial histological examination that was later reevaluated due to lack of clinical correlation. Three previously-reported cases of medallion-like dermal dendrocyte hamartoma also have had a previous histological misdiagnosis of probable neurofibroma; other reported cases have been misdiagnosed as congenital atrophic dermatofibrosarcoma protuberans. Clinical correlation and immunostaining are particularly important for the recognition of this rare benign lesion.

CD34-reactive tumors of the skin. An updated review of an ever-growing list of lesions

Over the past few years, a growing number of cutaneous tumors expressing CD34 is being reported. The list contains benign and malignant neoplasms as well as reactive and hamartomatous lesions of diverse lineages of differentiation, including fibroblastic, myofibroblastic, fibrohistiocytic, vascular, neural, adipocytic, smooth muscle, hematopoietic, melanocytic and epithelial. The more frequent diagnostic difficulties are found in spindle cell proliferations, mainly in those of the fibrocytic lineage. In part, this is because of the fact that in this area are, aside to well-defined entities, histologically and clinically diverse, recently reported cutaneous CD34-reactive lesions, whose definitions, limits and relationships are not completely established. The CD34 expression plays a key role in the differential diagnosis of some tumors, such as dermatofibrosarcoma protuberans, epithelioid sarcoma or pleomorphic hyalinizing angiectatic tumor of soft parts, with important therapeutic consequences. In others, as in desmoplastic trichilemmoma, it can help to resolve diagnostic problems in concrete cases. Finally, in many of the CD34-positive lesions, the diagnosis with the hematoxylin and eosin stain is straightforward. However, in all of them, the knowledge of the immunohistochemical profile contributes to our understanding of the cutaneous pathology.

Medallion-like dermal dendrocyte hamartoma

Medallion-like dermal dendrocyte hamartomas are rare congenital cutaneous lesions, with only three occurrences reported in the English language literature. They present at birth as asymptomatic circular, oval, or triangular well-circumscribed, atrophic patches. Typically, they have an erythematous or yellow-brown hue and a characteristic pliable, wrinkled surface; subtle telangiectases may also be appreciated. They may be misdiagnosed as atrophoderma, cutis aplasia, or anetoderma. All reported patients have been female. Characteristic histologic findings include epidermal atrophy and the presence of a CD34-positive spindle cell proliferation in the dermis. This spindle cell proliferation represents a population of dermal dendrocytes, which are bone marrow-derived cells that are believed to function as antigen-presenting cells that contribute to the function of the skin immune system. Little is known about the pathophysiology of medallion-like dermal dendrocyte hamartomas. We present a patient with this entity and review similar presentations reported in the literature.

Primitive Nonneural Granular Cell Tumors of Skin

A rare subset of distinctive cutaneous nonneural granular cell tumors was described by LeBoit et al in 1991 and termed "primitive polypoid granular-cell tumor." Herein, we report our experience with 13 similar, distinctive nonneural granular cell tumors. Affected patients included 7 males and 6 females ranging in age from 5 to 83 years (mean, 25 years; median, 16 years). These cutaneous lesions involved the back (5 cases), neck, shoulder, thigh (2 cases each), chin, and elbow (1 case each). Clinically described as smooth, nontender cutaneous nodules, the tumors ranged in size from 0.2 to 2.8 cm (median, 0.8 cm) and were present from months to years before excision. Mitoses numbered from 1 to 6 per mm (median, 2). Eight of the lesions were polypoid, based in the papillary dermis with extension to the superficial dermis and associated with an epithelial collarette. Five of the lesions were situated deeper in the reticular dermis with limited extension into the subcutis but clinically were also nodular. All the tumors were well circumscribed and composed of spindled to ovoid cells with abundant granular, eosinophilic cytoplasm and vesicular nuclei with small prominent nucleoli. Immunohistochemistry revealed reactivity only for NKI-C3 (11 of 12 cases), CD68 (7 of 11 cases), and NSE (5 of 10 cases); S-100 protein as well as other melanocytic, epithelial, and myoid markers were uniformly negative. All 13 of the lesions were locally excised and in the 8 cases with adequate follow-up ranging from 13 to 126 months (mean, 68 months; median, 41 months), none has recurred locally. However, one tumor (case no. 11) gave rise to a local lymph node metastasis 25 months after presentation, but the patient is currently disease-free 70 months after lymphadenectomy. These cutaneous granular tumors do not appear to be neural or Schwannian in nature, but their precise line of differentiation is unknown.

Histomorphologic and immunophenotypic analysis of fibrofolliculomas and trichodiscomas in Birt-Hogg-Dube syndrome and sporadic disease

BACKGROUND

Fibrofolliculomas and trichodiscomas are benign dermal neoplasms that likely derive from the mantle of the hair follicle and can occur sporadically or in association with Birt-Hogg-Dube syndrome (BHDS). Little is known about the pathogenesis and immunophenotypic properties of these entities.

METHODS

We investigated the histomorphologic and immnophenotypic properties of 15 fibrofolliculomas and trichodiscomas in two patients with BHDS and eight with sporadic disease.

RESULTS

We found the following: (1) fibrofolliculomas and trichodiscomas occurring in the setting of BHDS show microscopically contiguous histomorphologic features as compared to those occurring sporadically; (2) the immunophenotypic characteristics of syndromic-associated and sporadic types are identical and consist of (3) perifollicular vimentin (+), CD34 (+) and Factor XIII (-) spindle cells.

CONCLUSIONS

Despite subtle histomorphologic differences, trichodiscomas and fibrofolliculomas are immunophenotypically similar, and are thus likely derived from a similar histogenic precursor. Given the previously reported CD34 (+) immunophenotype of the hair mantle, our findings would support an origin of these lesions from the mantle of the hair follicle. The proliferation of CD34 (+) spindle cells seen in conjunction with these lesions should not be confused with other CD34 (+) dermal entities.

Congenital granular cell tumors localized to the arm

We report an instance of congenital granular cell tumors localized to the arm of a female infant. While granular cell tumors are well described during infancy as congenital epulis of the oral cavity, this case is unusual in both its location and histologic characteristics. The lesions, located around the antecubital fossa, were comprised of CD34-positive, S-100-negative granular cells. In addition, there were numerous eccrine glands in the upper dermis. The salient features of the case are discussed and reviewed in the context of the literature pertaining to this unusual entity.